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United States Patent | 6,213,605 |
D'Souza ,   et al. | April 10, 2001 |
A method for analysis of the curvature of the surface of a cornea using a checkered placido comprises, projecting the image of the checkered placido onto a patient's cornea, detecting the image of the checkered placido reflected off of the cornea, detecting a plurality of nodal points from the reflected image, determining the mean curvature at a plurality of nodal points and analyzing the mean curvature at a plurality of nodal points in order to produce a graphic display of the estimated actual curvature of the cornea.
Inventors: | D'Souza; Henry M. (Cypress, TX); Sarver; Edwin J. (Merritt Island, FL); Wakil; Youssef S. (Houston, TX) |
Assignee: | LaserSight Technologies, Inc. (Winter Park, FL) |
Appl. No.: | 102839 |
Filed: | June 23, 1998 |
Current U.S. Class: | 351/212 |
Intern'l Class: | A61B 003/10 |
Field of Search: | 351/200,205,206,211,212,221,246,247 |
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Dioptral curvature Surface radius in mm 61.0 5.53 60.0 5.63 47.0 7.18 45.0 7.50 44.0 7.67 42.0 8.04 41.0 8.23